More women may need breast cancer gene test, U.S. guidelines say

This undated fluorescence-coloured microscope image made available by the National Institutes of Health in September 2016 shows a culture of human breast cancer cells. (Ewa Krawczyk/National Cancer Institute via AP)

More women may benefit from gene testing for hereditary breast or ovarian cancer, especially if they’ve already survived cancer once, an influential health group recommended Tuesday.

At issue are genes called BRCA1 and BRCA2. When they’re mutated, the body can’t repair damaged DNA as well, greatly increasing the chances of breast, ovarian and certain other cancers. Gene testing allows affected women to consider steps to lower their risk, such as when actress Angelina Jolie underwent a preventive mastectomy several years ago.

Most cancer isn’t caused by BRCA mutations — they account for 5% to 10% of breast cancers and 15% of ovarian cancers — so the gene tests aren’t for everyone. But mutations cluster in families, and the U.S. Preventive Services Task Force has long recommended that doctors screen women who have relatives with BRCA-related cancers and refer those who might benefit from gene testing to a genetic counsellor to help them decide.

Take, for example, someone who had a tumour removed in one breast in their 40s a decade ago, when genetic testing wasn’t as common. Even this many years later, a BRCA test still could reveal if they’re at risk for ovarian cancer — or at higher than usual risk for another tumour in their remaining breast tissue, explained task force member Dr. Carol Mangione of the University of California, Los Angeles. And it could alert their daughters or other relatives to a potential shared risk.

“It’s important to test those people now,” Mangione said. “We need to get the word out to primary care doctors to do this assessment and to make the referrals.”

Private insurers follow task force recommendations on what preventive care to cover, some at no out-of-pocket cost under rules from former President Barack Obama’s health care law. The recommendations were published in the Journal of the American Medical Association.

Cancer groups have similar recommendations for BRCA testing, and increasingly urge that the newly diagnosed be tested, too, because the inherited risk can impact choices about surgery and other treatment.